The Xtreme clutches used to be good a couple of years ago, but they've changed something and they now fail way to often. I've had mine fall apart and got the same line - because i was drag racing, which i was, but it fell apart on me a couple of weeks after at PI. So i got them to fix it up and we put it back in. It's now not fully disengaging properly, once your moving it's ok, but its a pain to get into gear when still.
It's a pitty because they are nice clutches to drive, and don't slip.